VO2maxiin

VO2maxiin is a term used in theoretical discussions to describe a proposed composite metric of cardiorespiratory fitness. It is not a standardized measure in exercise science, and there is no widely accepted definition or calculation as of the mid-2020s. The term appears mainly in speculative models and fitness discourse rather than in peer-reviewed protocols.

Origin of the term combines VO2max, the maximal rate of oxygen uptake during intense exercise, with the suffix indicating an integrated index. In this context, VO2maxiin is intended to convey the idea of blending oxygen delivery capacity with additional endurance-efficiency components.

Conceptually, VO2maxiin would be a single score that reflects both aerobic capacity and endurance efficiency. Proposals describe combining VO2max with factors such as running economy, lactate threshold, and VO2 kinetics to produce a unitless or normalized value. Some hypothetical approaches envision using submaximal test data or wearable-tracking metrics to estimate the efficiency component. However, there is no validated protocol.

Limitations and interpretation: The lack of standardization and scientific validation means VO2maxiin cannot be used reliably for clinical assessment, prescription of training, or comparison across individuals. Critics warn that merging distinct physiological domains can obscure important differences between capacity, economy, and metabolic health.

See also VO2 max, lactate threshold, running economy, VO2 kinetics.